Figure. 7: Icatibant is a G protein-biased agonist for MRGPRX2 and inhibition of degranulation by resveratrol:

(A and B) RBL-MRGPRX2 cells were cultured in the absence or presence of PTx (100 ng/mL, 16 h) and percent degranulation and Ca²⁺ mobilization in response to Icatibant (20 μg/mL) was determined as described for compound 48/80 and AG-30/5C (Figure 2). (C) RBL-MRGPRX2 and (D) LAD2 cells were incubated with resveratrol (100 μM, 5 min), stimulated with Icatibant (20 μg/mL) for 30 min and percent degranulation was determined. (E) HTLA cells expressing MRGPRX2 (HTLA-MRGPRX2) were exposed to medium (Control) or resveratrol (100 μM of 5 min) followed by overnight stimulation with compound 48/80 (10 μg/mL) or Icatibant (30 μg/mL) and chemiluminescence was measured (F) Representative Ca²⁺ traces for compound 48/80 (30 μg/mL) and Icatibant (30 μg/mL) in HTLA-MRGPRX2 cells are shown. Statistical significance was determined by non-parametric t-Test and two way ANOVA. *** indicates P value<.001,** indicates P value <.01 and * indicates P value <.05.